Microsoft Virtual Academy

Module 3

Creating and Managing Virtual Hard Disks, Virtual Machines,

and Checkpoints

Module Overview

Creating and Configuring Virtual Hard Disks

Creating and Configuring Virtual Machines

Installing and Importing Virtual Machines

Managing Virtual Machine Checkpoints•Monitoring Hyper-V

Lesson 1: Creating and Configuring Virtual Hard Disks

What Are the Storage Options for Virtual Machines?

Overview of the Hyper-V Virtual Hard Disk Formats

Fixed Size and Dynamically Expanding Virtual Hard Disks

Differencing Virtual Hard Disks

Directly Attached Storage

Virtual Hard Disk Sharing and Quality of Service Management•Hyper-V Considerations for Virtual Hard Disk Storage

What Are the Storage Options for Virtual Machines?

•Virtual hard disk and directly attached disks•Support two storage controller types:

• Fixed size, dynamically expanding or differencing disk files

• Directly attached disks—local, or on iSCSI or Fibre Channel SAN

IDE SCSI

Only for Generation 1 virtual machines

For Generation 1 and Generation 2 virtual machines

Two controllers—Two devices per IDE controller

Four controllers—64 devices per SCSI controller

Virtual machine starts from IDE Only Generation 2 starts from SCSI

Cannot modify devices while virtual machine is running

Can modify devices when virtual machine is running

Overview of the Hyper-V Virtual Hard Disk Formats

• .vhd• Up to 2,048 GB in size

• .vhdx• Up to 64 TB in size• Internal log for enhanced resiliency• User defined metadata• Large disk sector support• Larger sector size (improved performance)• Default format in Windows Server 2012 R2

•Can convert between both formats• .vhdx recommended, if not used on older versions of Hyper-V

Fixed Size and Dynamically Expanding Virtual Hard Disks

Fixed size Dynamically expanding

Allocates all storage• Larger initial size• Creation takes time

(without Windows Offloaded Data Transfers)

Allocates space as needed• Smaller initial size• Created faster

Minimize fragmentation Can cause fragmentation

Cannot over-commit Can over-commit

Better performance (older Hyper-V)

Comparable performance (Windows Server 2012)

Use in production Use in testing and development

Differencing Virtual Hard Disks

• Stores changes from the parent disk• Parent disk should not change• Differencing disk isolate changes• Multiple differencing disks can use same

parent• Increases overhead (lower performance)

• Can be used for standardized base images• Should avoid in production

1234

File C

xxxx3

1234 1234

File A File B

1234

File D

Read Modify DeleteCreate

Read-Only

Grow

Directly Attached Storage

•Virtual machine directly accesses physical disk• Internal or LUN attached to Hyper-V server

• Disk must be offline before it can be used

• LUN on iSCSI or Fibre Channel SAN

•Pass-through disk considerations• Best performance• Unlimited size, lowest CPU utilization• No checkpoints or differencing virtual hard disks• No portability and encapsulation• Not included in Hyper-V backup

Virtual Hard Disk Sharing and Quality of Service Management

•Provides shared storage for virtual machines• Used as shared SAS disk by virtual machines• Virtual hard disk must be using VHDX format

• Must be connected to virtual SCSI controller• Must be stored on failover cluster

• CSV• Scale-out file server with SMB 3.0

• Separation between infrastructure and virtual machines

•Storage QoS restrict disk throughput• Configured per virtual hard disk• Dynamically configurable while virtual machine is running

Hyper-V Considerations for Virtual Hard Disk Storage

•Virtual hard disks consume large amounts of space• Can increase over time, implement monitoring

•Use multiple physical disks for better throughput• Use redundant storage spaces• SSD dramatically increases performance

•SMB 3.0 file share•Use SAN for storing virtual hard disks• Specialized, redundant, fast• Shared storage for failover clustering

•Exclude VHDs from antivirus scanning

Lesson 2: Creating and Configuring Virtual Machines

What Are the Components of a Generation 1 Virtual Machine?

Overview of Generation 2 Virtual Machines

Configuring Virtual Machine Settings

What Is Dynamic Memory?•What Is Smart Paging?•Overview of Integration Services•Using a Virtual Fibre Channel Adapter

What Are the Components of a Generation 1 Virtual Machine?

•Virtual machine has virtual hardware devices•Only devices that Hyper-V supports can be used•Virtual hardware can be:• Emulated – available during boot• Synthetic – available in supported operating systems• SR-IOV – available in supported operating systems

•Prior to Windows Server 2012 R2, only Generation 1 virtual machines were available

Overview of Generation 2 Virtual Machines

•Emulated devices are removed•UEFI firmware instead of BIOS• Secure boot• Boots from SCSI controller• PXE boot uses a standard network adapter

• Faster boot and operating system installation•Can run side by side with Generation 1• Generation 1 must be used for legacy systems

•Supported guest operating systems• Windows Server 2012 and Windows Server 2012 R2• 64-bit versions of Windows 8 and Windows 8.1

Configuring Virtual Machine Settings

• Only limited options are available during creation• Many more options are available after the virtual machine is created

• Configuration options depend on the generation of the virtual machine

• Most settings can be configured only if turned off• Adding or removing hardware components• Configuring memory, processor, disk settings• Few settings are configurable while virtual machine is running• Connecting a network adapter to a virtual switch• Adding a virtual hard disk to a SCSI controller• Enable or disable Integration Services

• Use Hyper-V Manager or Windows PowerShell• Set-VM, Add-VMHardDiskDrive, Add-VMNetworkAdapter

What Is Dynamic Memory?

• More efficient use of available physical memory• Shared resource that can be reallocated automatically

• Demand, available memory, and virtual machine memory settings

• Dynamic memory settings• Startup RAM

• Operating system typically requires more memory when started

• Minimum RAM• Can be decreased while virtual machine is running

• Maximum RAM• Can be increased while virtual machine is running

• Memory buffer• Percentage of extra memory to reserve for a virtual machine

• Memory weight• Prioritizes memory allocation when physical memory is low

What Is Dynamic Memory?

T = 0 T = 15 T = 30

2 GB

4 GB

6 GB

8 GB

Virtual MachinesMemory Settings

Total System MemoryMemory in Use by virtual machines

8 GB3 GB

Physical Memory Used 37.5 %

Finance virtual machine

Sales virtual machine

Engineering virtual machine

What Is Dynamic Memory?

T = 0 T = 15 T = 30

2 GB

4 GB

6 GB

8 GBFinance virtual machine

Sales virtual machine

Engineering virtual machine

Total System MemoryMemory in Use by virtual machines

8 GB6 GB

Physical Memory Used 75 %

Virtual MachinesMemory Settings

What Is Dynamic Memory?

Engineering reaches max allocation

T = 0 T = 15 T = 30

Finance virtual machine

Sales virtual machine

Engineering virtual machine

Service virtual machine

2 GB

4 GB

6 GB

8 GB

Total System MemoryMemory in Use by virtual machines

8 GB7,5 GB

Physical Memory Used 94 %

Virtual MachinesMemory Settings

What Is Smart Paging?

•Memory Management technique that uses physical disk resources as temporary memory• Ensures that a virtual machine can always restart• Used during virtual machine restart only

• If Hyper-V is low on memory, and• The virtual machine has more startup than minimum

RAM, and• Memory cannot be reclaimed from other virtual

machines

• Temporarily degrades virtual machine performance• Used only for a limited time, and then removed

• Not used when a virtual machine started from the Off state• Virtual machine operating system paging is always

preferred

What Is Smart Paging?

T = 0 T = 15 T = 30

Finance virtual machine

Sales virtual machine

Engineering virtual machine

Service virtual machine

2 GB

4 GB

6 GB

8 GB Virtual MachinesMemory Settings

Total System Memory 8 GB

• Sales virtual machine and Service virtual machine can be restarted only if Smart Paging is used

Overview of Integration Services• Makes a guest operating system aware that it is running on a virtual machine• Many operating systems include integration services• Install the latest integration services• VMBus and synthetic devices support• Time synchronization, mouse release, VSS

• Managed as virtual machine settings

Overview of Integration Services

Without Integration Services With Integration Services

Using a Virtual Fibre Channel Adapter• Access to Fibre Channel SAN storage from virtual machine• Hyper-V server has Fibre Channel HBA• Use Virtual SAN Manager to configure a virtual SAN

• Virtual Fibre Channel adapter maps to the physical HBAs• Virtual Fibre Channel adapter connects to the Virtual SAN

• Storage hardware must support N_Port ID virtualization• Virtual machine can have four virtual Fibre Channel adapters Supported Not supported

Virtual machine live migration

Boot from Fibre Channel SAN

Virtual machine failover cluster

Checkpoints

MPIO - multiple paths to SAN

Host-based backup

Live migration of SAN data

Lesson 3: Installing and Importing Virtual Machines

Virtual Machine Installation Methods

Importing Virtual Machines

Virtualizing a Physical Computer

The Virtual Machine Connection Application•Overview of Enhanced Session Mode

Virtual Machine Installation Methods• Install from a bootable CD/DVD-ROM• Single virtual machine can only use physical media at one time

• Install from an .iso file• Multiple virtual machines can use .iso file

• Install from a network-based installation server• Generation 1 – legacy network adapter required

•Copy virtual hard disk file with operating system installed• Similar to computer cloning• Virtual hard disk should first be generalized

•Use differencing virtual hard disks• Parent virtual hard disk should first be generalized• Parent virtual hard disk must not change

Importing Virtual Machines

• You can import a virtual machine without first exporting it• Only virtual machine data files are needed• Over 40 different types of issues detected, such as:

• Missing parent virtual hard disk• Virtual switch not available• Virtual machine has more processors than available

• Import process:• Creates a copy of the virtual machine configuration file• Validates hardware configuration settings• Compiles a list of incompatibilities• Displays incompatibilities and asks for new settings• Removes the configuration file copy

• Cannot start older saved states and checkpoints

Virtualizing a Physical Computer•Converting a physical computer to a virtual machine•Hyper-V does not include P2V functionality•Hyper-V can copy content of data disks• Configure disk in New Virtual Hard Disk Wizard• Copy entire disk, not volume or partition• Supported only for data, system disks are not supported

•Disk2vhd• Creates virtual hard disks• Uses VSS• Captured system has same identity

•Add virtual hard disk to virtual machine

Virtualizing a Physical Computer

The Virtual Machine Connection Application

•Connects to virtual machines on local and remote Hyper-V• Port 2179 used (can be modified in the registry)• Connection allowed by Windows Firewall• Installed as part of Hyper-V role or RSAT feature

• Single users can connect to virtual machines• Remote Desktop in virtual machines is not used

•Hyper-V Administrators can connect to virtual machines• You can restrict access to virtual machines• Revoke-VMConnectAccess cmdlet

Overview of Enhanced Session Mode•Remote Desktop connection to a virtual machine• Virtual machine can be without network connectivity• Devices can be redirected

• Printers, drives, smart cards, audio, other PnP devices• Shared clipboard, enhanced copy• Folder redirection

• RDS component is used• User must sign in to virtual machine• Remote Desktop Users group membership required

• Enabled at Hyper-V virtual machine connection and virtual machine level•Guest operating system support required• Windows Server 2012 R2 or Windows 8.1 • Available only when the virtual machine is running

Lesson 4: Managing Virtual Machine Checkpoints

What Are Virtual Machine Checkpoints?

Implementing Hyper-V Checkpoints

Overview of Checkpoints at File Level

Exporting Virtual Machines and Checkpoints

Issues with Checkpoints in Distributed Environments•Checkpoints and Virtual Machine Generation ID

What Are Virtual Machine Checkpoints?

• Checkpoint is a point-in-time virtual machine state• Can be taken if virtual machine is not in Paused state• Contains virtual machine configuration, memory and disk

state• Does not affect the running state of a virtual machine

• Primarily used for testing and development• Can cause issues in distributed production environment• Create differencing disk – decrease performance

• Cannot be created for directly attached disks• Used by Hyper-V Replica or in VDI deployments

Implementing Hyper-V Checkpoints•When created, a checkpoint cannot be modified• Only viewed, applied, exported, renamed, or deleted

•Checkpoint creation steps:1. Pause virtual machine

2. Create differencing disk for each disk that virtual machine is using

3. Create a copy of virtual machine configuration

4. Resume virtual machine

5. Copy virtual machine memory to disk

•Checkpoint consists of• Configuration file (*.xml)• Saved state file (*.vsv)• Memory content (*.bin)• Differencing disks (*.avhd)

Overview of Checkpoints at File Level

Snapshot

Apply (= delete Now)

Delete (= merge)

Apply (create branch)

Delete (= delete)

.vhd.avhd

Exporting Virtual Machines and Checkpoints

• Exporting a virtual machine is not required• You can copy virtual machine files

• Exporting virtual machine consolidate its files• If differencing drives are used, the entire hierarchy is exported• Exporting multiple virtual machines increases total size

• When exporting a virtual machine, all its checkpoints are exported

• Exporting a checkpoint exports only a single state• Differencing disks in checkpoint hierarchy are merged

• Live export – you can export while a virtual machine is running•Update integration services after import• Discard memory content and saved state from different architecture or pre-Windows 2012 Hyper-V

Issues with Checkpoints in Distributed Environments

•Applying a checkpoint takes a virtual machine back to a previous state•Can have serious implications and result in corruption• Vector-clock synchronizations are impacted

• Distributed applications depending on increasing logical clock• AD DS, DFS Replication, SQL Server replication

• Applying checkpoint rolls back the logical clock• Members of replica set to not converge to the same state

• Cryptography - reducing entropy of the random data • Distributed applications using vector clock algorithms have no awareness of running in a virtual environment• Removes changes in virtual machine as if they never happened• User data is lost, passwords are reverted

• Regardless of whether they were already synchronized or replicated

Issues with Checkpoints in Distributed Environments

Tim

e

DC1

T1

Replication to DC2: USN >100

Replication to DC2: USNs >200

DC1(A)@USN = 200

DC1(A) @USN = 250

ID: A

USN: 100 Create

Checkpoint RID Pool: 500 - 1000

+100 users

ID: A

USN: 200

RID Pool: 600 - 1000

ID: A

USN: 100 Apply T1 Checkpoint RID Pool: 500 - 1000

ID: A

USN: 250

+150 users

RID Pool: 650 - 1000

T2

T3

T4

Only 50 users are replicated to both domain controllers. Others are either on first or second domain controller. 100 users (RID 500-599) have duplicated SIDs.

DC2

Checkpoints and Virtual Machine Generation ID

• Designed to address issues of reverting to a past state• 64-bit integer, tied to a virtual machine configuration• Generation ID passed to a virtual machine in the BIOS

• Application can compare current and previous values• If values differ, then something happened to virtual machine

• Hypervisor must support virtual machine generation ID• Operating system in virtual machine must be generation ID-aware

Virtual machine generation ID change

Does not change

Virtual machine starts from checkpoint

Virtual machine is live-migrated

Virtual machine restored from backup

Virtual machine is paused or resumed

Virtual machine is migrated Virtual machine is restarted

Virtual machine is imported Hyper-V server is restarted

Checkpoints and Virtual Machine Generation ID

Checkpoints and Virtual Machine Generation ID

Checkpoints and Virtual Machine Generation ID

Lesson 5: Monitoring Hyper-V

Overview of Performance Monitoring

Monitoring a Hyper-V Host

Monitoring Virtual Machines•Resource Metering in Hyper-V

Overview of Performance Monitoring

•Monitors operating system and applications using system resources•Provides up-to-date information on performance• Health of the IT infrastructure

• Compare current activity with the baseline

• Planning for future requirements• Whether current performance is sufficient

• Identifying issues• Detecting problems• Proactive (real-time) and reactive (historical data)

•Windows Server 2012 R2 includes several tools•Operations Manager centralizes monitoring, alerting, and reporting for the enterprise

Overview of Performance Monitoring

Task Manager provides local, real-time performance data• Helps to identify and resolve performance-

related issues

Overview of Performance MonitoringResource Monitor provides in-depth real-time performance data • CPU, Memory, Disk, Network

Overview of Performance Monitoring

Event Viewer shows events that relate to server activity• Collected locally and remotely• Filtering, custom views, attaching tasks to the

events

Overview of Performance Monitoring

Reliability Monitor provides an historical view of server reliability and associated events

Overview of Performance Monitoring

Performance Monitor provides real-time monitoring and viewing of historical data gathered by data collector sets• Additional performance objects added with server

roles

Monitoring a Hyper-V Host

•Only Performance Monitor can monitor Hyper-V• Many Hyper-V performance objects added• Other tools monitor only their virtual environment

• Parent partition is also considered a virtual machine

•Memory, disk and network monitored the same• \Logical Disk(*)\Avg. Disk sec/Read and /Write• \Memory\Available Mbytes• \Network Interface(*)\Bytes Total/sec

•Processor utilization based on available resources• Hyper-V allocates resources to each virtual machine• \Processor(*)\% Processor Time shows relative utilization• \Hyper-V Hypervisor Logical Processor(_Total)\% Total Run Time should be used

Monitoring Virtual Machines

• Virtual machine tools monitor the virtual environment• Heavy utilization in virtual machine does not mean that Hyper-V host is heavy utilized (and vice versa)

• Available resources adjusted based on server load

• Memory and disk counters are the same as on the server• Hyper-V performance counters should be used• Hyper-V Hypervisor\Virtual Processors• Hyper-V Hypervisor Logical Processor \% Guest Run Time

• Hyper-V Virtual Network Adapter(*)\Bytes/sec

• Limit the processor resources that the virtual machine can use

Resource Metering in Hyper-V

•Track resources used by virtual machine or pool• Processor, disk, memory, network

•Can be used for charge back•Resource metering data follows a virtual machine•Configure by using Windows PowerShell• Enable-VMResourceMetering, Measure-VM

• Average CPU usage• Average physical memory usage• Minimum/maximum memory usage • Maximum amount of disk space allocated to a virtual

machine• Total incoming/outgoing network traffic for a network

adapter

•Graphical reporting is not included• Basic reporting in Windows PowerShell